I would think the easiest and neatest way to do this is to create a taxonomy for the menu/menu groups. Then setup links to the taxonomy categories (breakfast, lunch, appetizers, etc) through the website menu/sidebars. At that point all you would just need to add menu items like they were blog articles and style the archive pages to looks like a menu. I don’t think I’ve ever seen a menu plugin and I imagine it would be difficult to create a generic menu plugin since there are so many different types of restaurants that need to be taken into consideration – all of which would require different options and designs.